Guessing Where Gangs Will Grapple

California street gangs stage fights whose locations can be accurately predicted using the same algorithm anthropologists use to predict where lions and hyenas will fight in the wild to protect their territories. A UCLA researcher, using the standard "Lotka-Volterra" equation on 13 equal-sized criminal gangs in the Boyle Heights neighborhood in East Los Angeles, produced a table of probabilities showing how far from each gang's border any fights were likely to be. From 1999-2002, the formula correctly showed about 58 percent of shootings were within 0.2 miles of the border, 83 percent within 0.4 miles and 97 percent within 1 mile.